Drip irrigation hoses are in common use today. They are usually light, flexible plastic tubes with outlets, called emitters, located along them. These emitters allow water to slowly escape into the ground in order to irrigate the crop. Often fertilizers and other chemicals are added to the water for the benefit of the plants. These hoses are usually installed slightly underground to protect them from wind, rodents, sun, and machinery and to aid the flow of the water into the soil.
One of the problems of such a drip irrigation installation is that, if the grower does not irrigate enough to satisfy the needs of the plant, roots will grow to find more water. As the hose usually has some residual water left in it, the roots will seek the water, entering the emitter and eventually plugging it. When this process starts, uniformity of water distribution becomes erratic and shortly, unsatisfactory crop response results.
Root inhibiting chemicals may be passed through the hoses so as to destroy the roots of unwanted plants, but when the crop has been planted, the chemicals will also attack the crop.